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PubMed2004

Vipera palaestinae envenomation in 327 dogs: a retrospective cohort study and analysis of risk factors for mortality.

Vipera palaestinae (Vp), formerly a subspecies of the near east viper Vipera xanthina, is the most common poisonous snake in Israel and neighbouring countries (Jordan, Lebanon and Syria), and is responsible for most envenomations in humans and domestic animals. Hospital records were retrospectively reviewed for confirmed cases of Vp envenomations in dogs over a 13-year period and 327 cases were included in the study. Most envenomations occurred between May and October, and between 02:00 and 10:00 PM. The most frequent clinical signs included: local swelling and oedema (99.6%), viper teeth penetration marks (51%), tachypnoea (50%), panting (44%), increased body temperature (19.2%), tachycardia (>160/min, 19%), salivation (18%) and lameness (15.6%). Common haematological findings included: increased haematocrit (47%), increased haemoglobin concentration (45%), leucocytosis (39%), and thrombocytopenia (30%). The prothrombin time and activated partial thromboplastin time were prolonged in 68 and 21% of the dogs, respectively. Blood biochemistry abnormalities included increased activities of muscle enzymes, hyperglycaemia, hyperbilirubinaemia, hyperglobulinaemia and hypocholesterolaemia. The mortality rate was 4% (13 dogs). The following variables were significantly (p < 0.05) associated with mortality: body weight below 15 kg (p = 0.01), limb envenomation (0.008), envenomation at night (p = 0.025), severe lethargy (P < 0.001), hypothermia (p = 0.04), systemic bleeding (p = 0.001), shock (p = 0.007), dyspnoea (p = 0.002), tachycardia (p = 0.002), thrombocytopenia (p = 0.02), and glucocorticosteroid therapy (p = 0.002). Dogs younger than 4 years had a lower death risk (p = 0.01). The association of steroid therapy with increased mortality suggests that the use of steroids in Vp envenomations may be harmful. Specific antivenom therapy (10 ml/dog) was not associated with a higher survival rate, thus its use, dose and timing of administration should be further investigated.

Animals↗

PubMed1998

Preliminary evaluation of Vipera palaestinae snake bite treatment in accordance to the severity of the clinical syndrome.

The intravenous administration of a 60 ml dose of Vipera palaestinae antivenin was the suggested standard treatment of every bitten patient. In this study 85 Vipera palaestinae bitten patients where selectively treated with antivenin depending on the severity of the clinical picture. Patients who developed systemic or severe local signs received 20 ml of antivenin over 30 min. If symptoms were still present, an additional 10 ml of antivenin was given until systemic signs subsided. Repeated doses of 10 ml of antivenin was administered in each case of systemic symptom relapse. 49% of patients did not exhibit any systemic symptoms and did not receive antivenin treatment. In 63% of antivenin treated cases symptoms were aborted by a single dose of 20 ml of antivenin. 23% of the antivenin treated patients needed 30-40 ml, 19 needed 50-60 ml and only 1 patient (2%) received 80 ml of drug. Serum sickness complications were found in 44% of antivenin treated patients. The results of this study show that antivenin treatment based on systemic symptoms is effective, required less antivenin than the treatment with fixed dose for each patient and reduces the incidence of serum sickness.

Adolescent↗

PubMed1998

The Bov-B lines found in Vipera ammodytes toxic PLA2 genes are widespread in snake genomes.

In the fourth intron of two toxic Vipera ammodytes PLA2 genes a Ruminantia specific 5'-truncated Bov-B LINE element was identified. Southern blot analysis of Bov-B LINE distribution in vertebrates shows that, apart from the Ruminantia, it is limited to Viperidae snakes (V. ammodytes, Vipera palaestinae, Echis coloratus, Bothrops alternatus, Trimeresurus flavoviridis and Trimeresurus gramineus). The copy number of the 3' end of Bov-B LINE in the V. ammodytes genome is between 62,000 and 75,000. At orthologous positions in other snake PLA2 genes the Bov-B LINE element is absent, indicating that its retrotransposition in the V. ammodytes PLA2 gene locus has occurred quite recently, about 5 Myr ago. The amplification of Bov-B LINEs in snakes may have occurred before the divergence of the Viperinae and Crotalinae subfamilies. Due to its wide distribution in Viperidae snakes it should be a valuable phylogenetic marker. The neighbour-joining phylogenetic tree shows two clusters of truncated Bov-B LINE, a Bovidae and a snake cluster, indicating an early horizontal transfer of this transposable element.

Animals↗

PubMed1985

Opiomelanocorticotropic-like hormones in Vipera aspis pituitary.

By using immunohistochemical techniques (indirect immunofluorescence and PAP) adrenocorticotropic-like hormone (ACTH), alpha-melanocyte stimulating-like hormone (alpha-MSH), beta-lipotropic-like hormone (beta-LPH), and beta-endorphin-like (beta-EP) have been localized in the pituitary gland of newborn and adult Vipera aspis. The immunolocalization have been compared with the classical histochemical staining and the data show that the opiomelanocorticotropic-like cells resembles the B3 cells of the current literature. In the intermediate lobe both in adults and in newborns the same cells exhibit immunoreactivity for all the peptides considered, while in the rostral region of the pars distalis a difference has been observed between adults and newborns. In the adults, the cells immunostain for ACTH, beta-LPH, and beta-EP but not for alpha-MSH while in the newborns, the same cells show immunoreactivity for ACTH, beta-LPH, alpha-MSH but not for beta-EP. It has been hypothesized that in Vipera during maturation the pars distalis and the intermediate lobe can differently process the common precursor molecule.

Adrenocorticotropic Hormone↗

PubMed1998

Isolation, properties and N-terminal amino acid sequence of a factor V activator from Vipera lebetina (Levantine viper) snake venom.

A factor V activator (VLFVA) was separated from Vipera lebetina venom by gel filtration on Sephadex G-100 superfine, followed by chromatography on CM-cellulose and on heparin-agarose. This enzyme (VLFVA) with a molecular mass of 28.4 kDa, as determined by matrix assisted laser desorption ionization time-of-flight mass spectrometry, is a single-chain glycoprotein containing seven residues of neutral sugars, seven residues of hexosamines and three residues of neuraminic acid per molecule. The treatment with N-glycosidase F lowered the molecular mass approximately 6%. The N-terminal sequencing of VLFVA up to the 30th residue evidenced a high homology with Vipera russelli factor V activator RVV-Vgamma (90% identity). Aside from factor V, no other protein substrate for VLFVA has yet been identified. VLFVA hydrolyzes several synthetic arginine ester substrates, such as benzoylarginine ethyl ester (BAEE), tosylarginine methyl ester (TAME) and amide substrates such as Pro-Phe-Arg-MCA. The arginine ester hydrolase activity of the enzyme is markedly lower than that of the crude venom. The ability of VLFVA to activate factor V and its activity to BAEE and TAME were inhibited by the serine proteinase inhibitor, diisopropylfluorophosphate. VLFVA is thermostable protein, heating for 20 min at 70 degrees C does not alter the arginine esterase activity of the enzyme.

Amino Acid Sequence↗

PubMed2000

Cross-reactivities of polyclonal antibodies against factor V activating enzyme, a serine proteinase from Vipera lebetina (snake) venom.

Antibodies to the factor V activating enzyme from Vipera lebetina venom were produced by immunizing a rabbit with chromatographically purified factor V activating enzyme probes. The antibodies cross-reacted with different protein fractions in 23 snake venoms (ten viperid, eight crotalid, and five elapid venoms) as demonstrated by western immunoblotting. In the venom of Vipera russelli the antibodies recognized only one protein band which probably belonged to factor V activating enzyme.

Animals↗

PubMed1997

Enrichment of glutamate-like immunoreactivity in the retinotectal terminals of the viper Vipera aspis: an electron microscope quantitative immunogold study.

A post-embedding immunogold study was carried out to estimate the immunoreactivity to glutamate in retinal terminals, P axon terminals and dendrites containing synaptic vesicles in the superficial layers of the optic tectum of Vipera. Retinal terminals, identified following either intraocular injection of tritiated proline, horseradish peroxidase (HRP) or short-term survivals after retinal ablation, were observed to be highly glutamate-immunoreactive. A detailed quantitative analysis showed that about 50% of glutamate immunoreactivity was localized over the synaptic vesicles, 35.8% over mitochondria and 14.2% over the axoplasmic matrix. The close association of immunoreactivity with the synaptic vesicles could indicate that Vipera retino-tectal terminals may use glutamate as their neurotransmitter. P axon terminals and dendrites containing synaptic vesicles, strongly gamma-aminobutyric (GABA)-immunoreactive, were shown to be also moderately glutamate-immunoreactive, but two to three times less than retinal terminals. Moreover, in P axon terminals, the glutamate immunoreactivity was denser over mitochondria than over synaptic vesicles, possibly reflecting the 'metabolic' pool of glutamate, which serves as a precursor in the formation of GABA.

Animals↗

PubMed1978

Asynchrony in the synthesis of secretory proteins in the venom gland of the snake Vipera palaestinae.

1. Venom of Vipera palastinae was subjected to isoelectrofocusing on polyacrylamide gel. The protein separation profiles were similar for different venom samples; more than 25 protein bands with a wide range of pI values could be demonstrated by this technique. 2. Labelled venom was obtained 8h after an intracardial injection of [3H]leucine. The relative radioactivities of four out of 12 main protein bands were significantly different in the venom synthesized during the 2nd day of the venom regeneration cycle as compared with the venom of the 4th day. The comparison was made in venom samples obtained from the two glands of the same snake at two different secretory stages. 3. It is concluded that the asynchronous synthesis of exportable proteins after the initiation of a new venom regeneration cycle is responsible for the non-parallel secretion of some venom proteins by the venom gland of Vipera palaestinae during the first few days after milking.

Animals↗

PubMed1992

Characterization and molecular cloning of neurotoxic phospholipases A2 from Taiwan viper (Vipera russelli formosensis).

Two phospholipases A2 (PLA2s), designated as RV-4 and RV-7 were purified from venom of the Taiwan Russell's viper (Vipera russelli formosensis) by gel-filtration and reverse-phase HPLC. Their primary structures were solved by both protein sequencing and cDNA cloning and sequencing. The cDNA synthesized was amplified by the polymerase-chain reaction using a pair of synthetic oligonucleotide primers corresponding to the N- and the C-terminal flanking regions of the enzymes. The deduced amino acid sequences of RV-4 and RV-7 were 92% identical to those of the vipoxin and vipoxin inhibitor, respectively, from the Bulgarian Vipera a. ammodytes. RV-4 itself was neurotoxic, whereas RV-7 had much lower enzymatic activity and was not toxic. The low enzymatic activity of RV-7 may be attributed to five acidic residues at positions 7, 17, 59, 114 and 119, which presumably impair its binding to aggregated lipid substrates. Based on the sequence comparison among all the known group II PLA2s, residues 6, 12, 76-81, and 119-125 were identified as important for the neurotoxicity. RV-4 and RV-7 exist in the crude venom as heterodimers, which were again formed by mixing together the HPLC-purified RV-4 and RV-7. Moreover, RV-7 inhibited the enzymatic activity of RV-4 in vitro but potentiated its lethal potency and neurotoxicity. It is suggested that RV-7 may facilitate the specific binding of RV-4 to its presynaptic binding sites, probably by preventing its non-specific adsorption.

Amino Acid Sequence↗

PubMed2003

The effect of crude and purified Cerastes vipera venom protein fractions on respiratory chain function in cultured human fibroblasts.

This study was conducted to investigate the effect of crude and venom protein fractions of Cerastes vipera on the major enzymatic components of the respiratory chain in cultured human fibroblasts. Cerastes vipera crude venom was fractionated into seven protein fractions by using 8% preparative native polyacrylamide gel electro-phoresis. The effect of crude venom and purified venom fractions (F1-F7) on respiratory chain function in cultured human fibroblasts was investigated. Confluent fibroblast cultures were incubated with crude venom and venom protein fractions for a fixed period of three hours at 37 degrees C. Crude venom and venom protein fractions 2, 4, 5 and 6 significantly increased the production of lactate as compared to control fibroblasts. The production of pyruvate was markedly decreased in all these cell lines. The ratio of lactate/pyruvate was increased in the cells and in the culture medium by crude venom and venom protein fractions 2, 4, 5 and 6. On the other hand fractions 1,3 and 7 exhibited no effect in relation to lactate and pyruvate production. Similarly the crude venom protein and venom protein fractions 2, 4, 5 and 6 significantly lowered the activity of the major enzymatic component of the respiratory chain in fibroblast mitochondria. In conclusion it is apparent that the crude and venom protein fractions 2, 4, 5 and 6 resulted in a significant lowering of the mitochondrial respiratory chain activity in cultured human fibroblasts.

Animals↗

PubMed1987

Sequence homology between phospholipase and its inhibitor in snake venom. The primary structure of phospholipase A2 of vipoxin from the venom of the Bulgarian viper (Vipera ammodytes ammodytes, Serpentes).

The amino-acid sequence of phospholipase A2 from the neurotoxin vipoxin of the Bulgarian Viper (Vipera ammodytes ammodytes, Serpentes) is presented. The enzyme consists of 122 amino-acid residues including 7 disulfide bonds and thus belongs to phospholipases A2 group IIA. The sequence was determined by automatic Edman degradation of the intact chain and of the peptides obtained after tryptic hydrolysis of the oxidized chain. The short cleavage time of 30 min and another limited tryptic digestion of the oxidized and citraconylated chain provided overlapping peptides. Sequencing was done with liquid- and gas-phase sequenators. The complete alignment of all peptides was facilitated by the high degree of homology with known viperid venom phospholipases A2. In common with mammalian phospholipases, the tryptophan residue in position 30 (essential for enzymatic activity) as well as the histidine in position 47 in the active site are present. Vipoxin phospholipase A2 shows 53.3% homology with another phospholipase A2 from Vipera ammodytes ammodytes venom (Ammodytoxin B), whereas 62% homology was found between both subunits of vipoxin phospholipase A2 and its inhibitor. This high degree of identity can be accounted for in terms of a common origin by gene duplication.

Amino Acid Sequence↗

PubMedDate not supplied

Enzymatic activity and inhibition of the neurotoxic complex vipoxin from the venom of Vipera ammodytes meridionalis.

Vipoxin from the venom of Vipera ammodytes meridionalis is an unique neurotoxic complex between a toxic phospholipase A2 and a highly homologous non-toxic protein inhibitor. It is an example of evolution of a catalytic and toxic function into inhibitory and non-toxic one. The activity of the V. ammodytes meridionalis toxin is 1.7 times higher than that of the closely related (92% sequence identity) neurotoxic complex RV4/RV7 from the venom of Vipera russelli formosensis The enhanced enzymatic activity of vipoxin is attributed to limited structural changes, in particular to the substitutions G54R and Q78K in the PLA2 subunit of the complex and to the T54R substitution in the inhibitor. Oleyloxyethylphosphocholine, aristolochic acid and vitamin E suppressed the enzymatic activity of vipoxin and its isolated PLA2 subunit. These compounds influence inflammatory processes in which PLA2 is implicated. The peptide Lys-Ala-Ile-Tyr-Ser, which is an integral part of the PLA2 components of the two neurotoxic complexes from V. ammodytes meridionalis and V. russelli formosensis (sequence 70-74) activated vipoxin increasing its PLA2 activity by 23%. This is in contrast to the inhibitory effect of the respective pentapeptides with 70-74 sequences on other group II PLA2s. Surprisingly, the same peptide inhibited 46% of the V. russelli formosensis PLA2 activity. The limited changes in the structure of the two highly homologous neurotoxins lead to considerable differences in their interaction with native peptides.

Amino Acid Sequence↗

PubMed2004

[Envenoming by common viper (Vipera berus)--subject still exists...].

The only venomous reptile that naturally occurs in Poland is the adder or common viper (Vipera berus). Its bites are not of great epidemiological importance, but in some cases serious life-threatening symptoms may appear. The most common symptoms of adder envenomation are: local edema, reddening and pain of the bitten site and also the general symptoms coming from the alimentary tract (vomiting, diarrhoea, abdominal pain), the circulatory system (hypotension, shock, ECG abnormalities), the central nervous system (sleepiness, vertigo, disorientation, loss of consciousness), hematological symptoms (leukocytosis, hemolysis, coagulopathy) and allergic symptoms (fever, urticaria, angio-oedema). In the present study we described the case of a twenty-year-old patient hospitalized at the Toxicology Department of the Collegium Medicum UJ after a viper bite. Except for some above-mentioned symptoms he also developed ocular symptoms like ptosis and blurred vision. Such symptoms after the common viper bite have not been described in the literature till now. The cause of them seems to be an intense allergic reaction in the region of the orbit and eyelids all the more so because the patient had the positive allergy history. However, taking into account the latest reports from the literature, a neurotoxic action of some components of the Vipera berus venom may also play a role. Because of the developing general symptoms a specific equine antivenom was administered to the patient, apart from the supportive care, without any serious side effects that usually are observed after the use of such a kind of sera. It is thought that the sheep antivenom is better than the equine one considering a lack of allergic side effects. As a result of applied treatment the local and general symptoms including ocular symptoms subsided.

Adult↗

PubMed1984

Mode of neuromuscular blocking action of toxic phospholipases A2 from Vipera ammodytes venom.

The effects of toxic phospholipases A2 ( fraxtions "j", "k1" and "k2") isolated from the venom of Vipera ammodytes were studied on the chick biventer cervicis muscle and the mouse phrenic nerve-diaphragm preparations. In the chick muscle, all of these PLA2s caused neuromuscular (N-M) blockade without producing contracture or affecting the response of the muscle to acetylcholine. In the mouse diaphragm, these PLA2s inhibited completely the indirectly elicited contraction without affecting that evoked directly. The order of their N-M blocking potency is "k2" greater than "k1" greater than or equal to "j". In a low Ca2+ (0.5 mM) medium, they produced a triphasic change in the indirectly elicited contractions: an initial inhibition followed by an enhancement and then a progressive depression leading to complete N-M blockade. The frequency of miniature endplate potentials (m.e.p.p.s) in the mouse diaphragm first increased 2-3 fold and then gradually decreased after "k2" treatment, while the amplitude of m.e.p.p.s did not decrease even after the evoked release of transmitter failed. Giant potentials and bursts of m.e.p.p.s were frequently observed. The quantal content of e.p.p.s was first increased and then decreased gradually. The resting membrane potential was only slightly reduced at 30 micrograms per ml. The ultrastructure of motor nerve terminals in the "k2"-intoxicated mouse diaphragm showed an increase in omega-shaped indentation in the axolemma. The mitochondria in the nerve terminal were swollen and vacuolized. No structural changes were found in the muscle fibers, fibrocytes and myelinated axons in the diaphragm. It is concluded that the toxic PLA2s from Vipera ammodytes venom produce a N-M blockade by acting selectively on the presynaptic site.

Action Potentials↗

PubMed1981

[Coagulant and anticoagulant action of Vipera berus venom on human blood].

The effect of Vipera berus venom on coagulation of human blood has been studied. PTT and coagulation time according to Quick of normal human plasma kept with Vipera berus venom (400 microgram/ml) for variable times have been misused. The venom has an immediate coagulant and, subsequently, anticoagulant effect.

Blood Coagulation↗

PubMed1994

Pharmacokinetics of Vipera aspis venom after experimental envenomation in rabbits.

Toxicokinetic studies of Vipera aspis venom were performed in rabbits after experimental envenomation. Venom proteins with a molecular weight greater than 6 kDa (high-molecular weight proteins) and which reacted in enzyme-linked immunosorbent assay with specific antiviper venom Fab'2, were also responsible for the lethal potency and the capillary permeability increasing activity of the venom. Conversely, low-molecular weight proteins were not detected by enzyme-linked immunosorbent assay and were pharmacologically inactive. The toxicokinetics of both classes of venom components were studied, using high-molecular weight and low-molecular weight radiolabeled proteins as well as enzyme-linked immunosorbent assay. After intravenous injection, Vipera aspis venom in plasma followed a biexponential decline with a distribution half-life of 0.7 hr and an elimination half-life of 12 hr. The distribution volume was 1.2 l.kg-1 and the systemic clearance was 84 ml.hr-1.kg-1. Venom levels in plasma after intramuscular injection of three doses (300, 500 and 700 micrograms/kg) of venom increased within the few hours after the venom administration to reach maximal values proportional to the injected doses. They subsequently followed a monoexponential decline, with an apparent terminal half-life of 32.5 hr. Absorption was a kinetically complex process, rapid during the first 24 hr and continued at a slower rate over the subsequent 72 hr. Bioavailability of venom was about 65%, regardless of the administered dose, and less than 5% of venom injected was excreted by the renal route.

Animals↗

PubMed1993

Decreased serum cholesterol level after snake bite (Vipera palaestinae) as a marker of severity of envenomation.

In 44 patients bitten by snakes (Vipera palaestinae), admission serum cholesterol levels were negatively correlated with severity of envenomation (mean +/- SD, 175 +/- 49, 137 +/- 36, and 96 +/- 40 mg/dl, respectively, in cases with mild, moderate, and severe clinical manifestations [p < 0.0001]). Concomitant decreases in serum albumin were not significant. These findings were supported by experimental results in rabbits, in which low, medium, and high doses of purified V. palaestinae venom (all in the non-lethal range), led to dose-dependent decreases in serum cholesterol, at 180 minutes, of 9.5% +/- 8.9%, 18.6% +/- 10.1%, and 32.7% +/- 11.8%, respectively (p < 0.01). This rapid decrease in serum cholesterol level is only partially explained by transcapillary lipoprotein leakage and probably indicates changes in lipoprotein transport and metabolism caused by the phospholipase A2 component of V. palaestinae venom. Admission total serum cholesterol level may serve as an indicator of severity of envenomation in patients bitten by snakes of the Vipera genus before full development of the clinical syndrome.

Adult↗

PubMed1997

Vipera berus and V. ammodytes (Serpentes:Viperidae) represent new host for Caryospora simplex (Apicomplexa:Eimeriidae) in Europe.

During a survey of the coccidian parasites of reptiles, caryosporan oocysts wee found in the faeces of wild and captive European viperid snakes Vipera berus (L.) and V. ammodytes (L.). Thirty two of 37 examined V. berus (86%) and 9 of 17 examined V. ammodytes (53%) specimens were found to be passing caryosporan oocysts. Morphological characters of all caryosporan isolates were identical and fitted well with the description of Caryospora simplex Léger, 1904. Experimental inoculation of severe combined immunodeficient (SCID) mice with seven isolates of C. simplex from V. berus or V. ammodytes confirmed the heteroxenous life cycle pattern, for the first time for isolates of evidently European origin. Caryosporan developmental stages were observed in the connective tissues of the nose, cheeks, ear and scrotum in all inoculated SCID mice. V. berus and V. ammodytes represent new hosts for C. simplex. The present paper represents the first widely based report on coccidian parasites of the genus Caryospora Léger in European viperids. Our findings indicate a wide distribution of C. simplex throughout the range of distribution of snakes of the genus Vipera.

Animals↗